Synthesis of heterocyclic compounds using the Nenajdenko-Shastin reaction

The use of a catalytic olefination reaction (the Nenajdenko-Shastin reaction) in the synthesis of heterocyclic compounds is discussed.     

环链转移反应及其在合成杂环化合物中的应用

概括了环链转移反应的类型、机理,同时综述了环链转移反应在合成取代杂环化合物中的应用。     

Simple and efficient MW-assisted cleavage of acetals and ketals in pure water

Simple and efficient MW-assisted cleavage of acetal and ketal is proposed in deionized water and in a very short time.     

A facile and efficient addition reaction of nitrogen‐containing heterocyclic compounds with DMAD under neat conditions

A simple and efficient method was developed for the reaction of dimethyl acetylenedicarboxylate with benzothiazole, isoquinoline, quinoline, 3‐bromopyridine, pyridine, benzoxazole, benzimidazole, and 5,6‐dimethyl benzimidazole for the high‐yield synthesis of the related heterocyclic products ( 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ) in very short reaction time under neat procedure. The reaction of isoquinoline, 3‐bromopyridine, and pyridine afforded to diastereomeric mixtures of products 2 , 4 , and 5 , respectively. However, only one isomer of products 1 , 3 , 6 , 7 , and 8 were identified from the reaction of benzothiazole, quinoline, benzoxazole, benzimidazole, and 5,6‐dimethyl benzimidazole, respectively. Benzotriazole afforded to product 9 under these conditions. For comparison, the reactions were examined in different reaction mediums and/or under microwave irradiation. J. Heterocyclic Chem., (2011).     

Hydrogenation of oxygen-containing heterocyclic compounds on group VIII metals

The hydrogenation of a number of oxygen-containing heterocyclic compounds on Pt, Pd, and Rh blacks in the liquid phase at atmospheric pressure was investigated. The results are compared with data on H-D exchange with D₂O and are interpreted from the point of view of the theory of -complex adsorption.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No.10, pp. 1332–1334, October, 1981.     

Pummerer reaction in synthesis and transformations of heterocyclic compounds (review)

Data on the use of the Pummerer reaction in the synthesis and transformations of various heterocyclic compounds that contain oxygen, sulfur, and nitrogen as the heteroatoms are correlated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1299–1313, October, 1989.     

Thiomethylation of aromatic amines: efficient method for the synthesis of heterocyclic compounds

Primary aromatic amines were thiomethylated by formaldehyde and hydrogen sulfide. N-Substituted 1,3-thiazetidines, 4,5-dihydro-1,3,5-dithiazines, 3,4,5,6-tetrahydro-2H-1,3,5-thiadiazines, and 4,5-dihydro-1,3,5-oxathiazines were prepared for the first time starting from meta- and para-toluidines, meta-, para-, and ortho-anisidines, and para-xylidine. Amines characterized by higher mobility of hydrogen atoms produced previously unknown four-membered thiazetidines, whereas amines characterized by lower mobility of hydrogen atoms gave six-membered thiadiazines. The sorption properties with respect to silver were studied for the compounds, which were prepared from p-toluidine and p-anisidine.     

Highly efficient Suzuki-Miyaura coupling of heterocyclic substrates through rational reaction design

A dicyclohexyl(2-sulfo-9-(3-(4-sulfophenyl)propyl)-9H-fluoren-9-yl)phosphonium salt was synthesized in 64% overall yield in three steps from simple commercially available starting materials. The highly water-soluble catalyst obtained from the corresponding phosphine and [Na(2)PdCl(4)] enabled the Suzuki coupling of a broad variety of N- and S-heterocyclic substrates. Chloropyridines (-quinolines) and aryl chlorides were coupled with aryl-, pyridine- or indoleboronic acids in quantitative yields in water/n-butanol solvent mixtures in the presence of 0.005-0.05 mol % of Pd catalyst at 100 degrees C, chloropurines were quantitatively Suzuki coupled in the presence of 0.5 mol % of catalyst, and S-heterocyclic aryl chlorides and aryl- or 3-pyridylboronic acids required 0.01-0.05 mol % Pd catalyst for full conversion. The key to the high activity of the Pd-phosphine catalyst is the rational design of the reaction parameters (i.e., the presence of water in the reaction mixture, good solubility of reactants and catalyst in n-butanol/water (3:1), and the electron-rich and sterically demanding nature of the phosphine ligand).     

The Mitsunobu reaction in the chemistry of nitrogen-containing heterocyclic compounds. The formation of heterocyclic systems (review)

Methods for the design of nitrogen-containing heterocyclic systems involving the formation of C-N bonds under the conditions of the Mitsunobu reaction are discussed. Dedicated to Afanasi Andreevich Akhrem on his 95th birthday. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 347–385, March, 2008.     

Insertion reaction of azidosulfonyl azo dye with model alicyclic and heterocyclic compounds

Thermal reactions of 4-(2-hydroxynaphthalen-1-yldiazenyl)benzenesulfonyl azide with cyclohexane, benzene, toluene, anisole, p-xylene, mesitylene, dihydropyran, and pyridine were studied. Structures of the resulting azo dyes were confirmed by FT-IR, UV, ¹H and ¹³C NMR, and mass spectra and elemental analyses, and their solvatochromic properties were examined. Probable mechanisms of nitrene insertion were discussed. Published in Russian in Zhurnal Organicheskoi Khimii, 2008, Vol. 44, No. 10, pp. 1488–1494. The text was submitted by the authors in English.     

N-Alkoxymethylation of heterocyclic compounds with diethyl phosphite via cleavage of P-O bond

N-Alkoxymethylation of heterocyclic compounds with diethyl phosphite via cleavage of P-O bond was investigated and a series of N3-ethoxymethylated heterocyclic compounds were synthesized. A mechanism in which diethyl phosphite acts as an efficient surrogate of ethanol was proposed and supported by several evidences.     

n-σ Mixing in pentatomic heterocyclic compounds of sixth group by photoelectron spectroscopy

The HeI photoelectron energy spectra of the tetrahydro derivates (CH₂)₄X (X = O, S, Se, Te) have been measured and interpreted on the basis of a local C_2V symmetry of the CH₂?X?CH₂ fragment. Mixing of the so called “non-bonding” electrons of the heteroatom with the σ_π system is apparent from the shape of the first photoelectron band and from a comparison of the absolute values of the first ionization energies with those of the corresponding H₂X molecules. Such mixing is the highest for the oxygen derivative and gradually decreases on going toward the tellurium compound.     

Reaction of 9-chloroacridine with heterocyclic compounds containing an active methyl group

9-Chloroacridine reacts with 4-picoline to form 1-(9-acridinyl)-4-(9-acridinylmethylidene)-1,4-dihydropyridine, whose structure was proved by chemical transformations. A number of such compounds were obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1090–1093, August, 1971.